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In this thread I will be documenting my exploration of the New Horizons planet pack, in addition to Asclepius which orbits the sun opposite Laythe. This will be quite a challenge as not only will I have to plan interplanetary maneuvers from a moon (as Kerbin now orbits the gas giant Sonnah) but I will be doing it at 3.2x scale and using Kerbalism (as well as manually reducing reaction wheel power to 5% to force the use of more realistic methods of attitude control).

The first installment of this series can be found here. For a brief summary, what has been done so far is a short sounding rocket program, followed by several attempts to get a space probe into Kerbin orbit, and then the first crewed space flight.

Pictured above is what is currently the only successful orbital launch vehicle: the Aptur-E rocket. Details about it can be found in the post previously linked.

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Good luck! New Horizons is a very fun system. I tried it in 1.1 and really enjoyed it. There was a problem back then, however. You couldn't leave anything unfocused in Kerbin orbit or it would either be ejected from the Sonnah system or de-orbited into Kerbin. This made things complicated. Hopefully, that problem is now fixed. I'm currently doing Alternis Kerbol where Kerbin is also a gas giant's moon and no problems with stuff in Kerbin orbit so far.

Still, I recommend testing the stability of Kerbin orbits before getting too far down the track of relying on stuff staying there.

Edited October 7, 2017 by Geschosskopf

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Thanks. I have actually played with New Horizons before, but this time I plan to explore a lot further than I have in the past (aside from testing, I've only legitimately visited Mun, Serran, Aptur, and the Jool system). It presents some interesting challenges and it also looks good, which is of course a plus.

As for relay satellites, I'm mostly only going to have relays in Sonnah orbit rather than Kerbin orbit, and likewise with space stations (aside from a couple early-game low-orbit stations, which aren't designed to last long anyway). I've actually had a bit of difficulty with antennas so far (as will be seen in the next mission upload), but mostly that's my own fault for not using a strong enough antenna.

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The Quicksilver program continues, now with an attempt to send Debdan Kerman to orbit. The spacecraft has seen a couple of modifications since Valentina's orbital flight, and now includes an experimental docking system, more power storage, and an improved attitude control system. Based on the previous launch, the upgraded spacecraft is still within the mass limit for the Aptur-F rocket.

Spoiler

Liftoff of Quicksilver-Aptur 2.

It seems that issues with the guidance system [I typed a few things into MechJeb wrong] have caused the rocket to pitch over too far, and as such it no longer has the ability to reach orbit.

The abort sequence is initiated. Debdan experienced high acceleration, but luckily she remained conscious. The landing sequence doesn't require control from the pilot, but it's not ideal if the pilot is unconscious.

The splashdown was successful and Debdan returned to the KSC.

Ultimately the problem with Quicksilver-Aptur 2 was due to the increased mass throwing off the guidance computers, but the thrust of the engines also played a part, as there was not enough thrust after the half-stage separated. The Quicksilver program will be put on hold for now.

K-SCI 1

K-SCI 1 is a satellite designed to study Kerbin's magnetic fields. As the name implies it is purely a science satellite. It is launched on an Aptur-E rocket.

Spoiler

Liftoff of K-SCI 1. Most of the launch footage will be skipped as it is identical to other launches of the Aptur-E rocket.

After fairing separation. The launch was nominal.

Circularizing with the Kinesis upper stage. The Kinesis stage will actually burn until all of its fuel is exhausted, and then the payload will use its own engines to raise its apoapsis above 2000km.

Payload deployment. It's worth noting that this is the first spacecraft to use solar cells for power.

The spacecraft deploys its instruments in preparation for studying Kerbin's magnetic field.

Once in its final orbit, K-SCI 1 conducts detailed ongoing surveys of Kerbin's magnetic field. Its orbit will eventually decay, but this will be after its mission is complete.

K-SCI 2

K-SCI 2 is an orbital telescope. It will be launched into a low polar orbit of Kerbin, and will make observations of the ground from space.

Spoiler

The launch occurs near dusk, to put the payload in an orbit above the day-night boundary. This is to ensure that it always has power. Its mission will be complete before Sonnah moves to a position which would put K-SCI 2 in darkness for half of its orbit.

Half-stage separation.

The payload after fairing deployment.

The satellite has to circularize using its own propulsion system, as a polar orbit takes more delta-v than an equatorial orbit.

The eventual orbit was slightly lower than intended, but it shouldn't decay before the satellite's mission is complete.

Serran 1

Following the failure of Quicksilver 2, the Quicksilver program has been cancelled in favor of the Serran program. This new crewed space program uses a two-kerbal spacecraft and the far-more-powerful Aptur 2 rocket (though eventually it will also use even larger rockets for heavier payloads). The name of the Serran program comes from its ultimate goal: crewed exploration of Serran, the farthest moon of Sonnah. It will see crewed missions to Aptur, Mun, and Eli as well, but Serran is the largest challenge and also the highest priority.

Serran 1 will test the docking system by docking with Serran 2, and it will also ascend into a higher Kerbin orbit to test re-entry at inter-lunar speeds. The crew of Serran 1 are Debdan Kerman and Gralorf Kerman.

Spoiler

Ignition. The Aptur 2 rocket is based on the Aptur-F, though with some obvious changes. The Kinesis stage is no longer an integral part of the rocket; its larger upper stage completes orbital burns. The half-stage assembly has been removed in favour of a slightly more powerful engine (which also has the ability to throttle to 60%), and two large solid rocket motors have been added for the extra thrust and delta-v required.

Liftoff of Serran 1.

Commencing gravity turn. These solid rocket motors are not only the largest used so far, but also the only ones in use with gimballed nozzles. This means that they will not cause control issues which would otherwise be expected from such large solid rocket motors on such a comparably-small vehicle.

Booster separation was very close as the separation motors failed. Luckily, however, there was not a serious collision so the launch can continue as normal.

First stage cutoff and separation, second stage ignition.

Second stage cutoff as 95km apoapsis is reached. The second stage engine is capable of restarting, which is vital for this sort of launch profile.

Circularizing.

Second stage separation. The Serran spacecraft has a set of boosters hidden within the white shroud. They run on monopropellant, and provide good performance for this spacecraft despite the low Isp of monopropellant thrusters. The vehicle is powered by a monopropellant fuel cell, which runs on the decomposition of the monopropellant fuel. And, very importantly, the spacecraft is capable of sustaining its two crew members in orbit for up to 5 days.

The crew of Serran 1 will now wait in orbit for Serran 2, and will initiate the rendezvous maneuver when the second spacecraft is in orbit.

Serran 2

Spoiler

Liftoff of Serran 2. The crew of this mission are Valentina Kerman and Janmon Kerman.

Disaster strikes at booster separation. Once again the separation motors failed, but this time the SRMs collided with the first stage and destroyed the interstage between the first and second stages.

The flight computer detected the lack of a first stage and ignited the second stage. By this time though, the abort sequence had already initiated, so the crew were accelerating away from the exploding rocket. They experienced a peak acceleration of 12.7g, which knocked Gralorf unconscious. The two of them will have to spend some time recovering before their next flight.

Service module separation.

The capsule reached an apoapsis of 70km before falling back to the surface. Acceleration was high on this descent, but not as high as when the launch escape system was firing.

The parachutes deployed successfully and splashdown went as expected.

The Serran program will be put on hold until the issues with the Aptur 2 rocket are solved.

Continuation of Serran 1

Spoiler

Though the docking test cannot take place without Serran 2, Serran 1 can still complete the other part of the mission. The spacecraft boosts into an orbit with a 1500km apoapsis, which just crosses Kerbin's inner magnetic field.

Currently this is the furthest any kerbals have been from Kerbin. The crew do a couple of science experiments in the high orbit, and record their observations.

Lowering apoapsis to 25km. This is a lower periapsis than usual, and combined with the higher apoapsis it will result in re-entry speeds comparable to a return from Sonnah orbit, which will use a periapsis of 40km.

Approaching the atmosphere.

Service module separation.

Re-entry goes as expected.

Re-entry was successful, and Serran 1 splashed down safely.

Athena 1

After some delays as tests were conducted on the Aptur 2 rocket to prevent further failures, the Serran program continues with the launch of the Athena 1 space station. Designed to sustain 2 kerbals in low Kerbin orbit for 30 days, Athena 1 will serve as a testing ground for future missions.

Spoiler

The launch begins nominally.

Booster cutoff and separation. This time the separation motors worked perfectly.

The launch continues nominally.

Fairing separation.

The second stage of the launch vehicle has been integrated into the payload to reduce complexity and additional mass, and also so that the station can be de-orbited once it is no longer needed. Forward of the station's propulsion module is the habitation module, and then the service module (which stores food, water, and oxygen as well as managing power), then the airlock, and finally the docking module. The station is powered by four new solar panels, which are capable of tracking the sun (though this feature is experimental).

The station is placed into a 95km parking orbit, and is then moved to its final 300km circular orbit.

Serran 3

Now recovered after the failure of Serran 2, Valentina and Janmon launch again on Serran 3. Their mission is to dock with the Athena 1 space station and do some experiments in orbit, while remaining in space for 30 days.

Spoiler

The upper stage has been augmented with de-orbit motors, which activate on separation. This is to prevent the buildup of debris in space, though the low parking orbit would result in orbital decay after a while anyway.

Several maneuvers are performed to rendezvous with the station.

Approaching Athena 1. Aptur can be seen here in the background.

Final approach to dock.

Docking successful. The first test is of the sun-tracking solar panels, so the station will rotate so that the opposite end of it is facing the sun.

The solar panels work as predicted. Though they provide adequate power for the station, the fuel cell in the Serran spacecraft is capable of powering the station for several days if necessary.

OOP1-Aptur

Finally, the time has come to send something beyond Kerbin orbit. Orbital Observation Platform 1 is a large space probe designed to study Aptur, the nearest of Sonnah's moons to Kerbin. Aptur shares the same orbital period as Kerbin but its orbit is slightly offset, in such a way that its motions resemble those of an object orbiting Kerbin itself. OOP1 has several pieces of imaging equipment for various wavelenths of light, and is currently the largest uncrewed spacecraft to be launched into space (Athena 1 is larger, but though it was launched without crew it is still considered a "crewed" spacecraft).

Spoiler

Liftoff of OOP1-Aptur.

OOP1 in Kerbin orbit. The inclusion of a Kinesis stage is technically not necessary, but the spacecraft might be repurposed in future so it's useful to have some extra delta-v. It may also need to change its orbit if a site of particular interest is found on Aptur.

The upper stage of the launch vehicle ignites to begin the ejection burn from Kerbin. At this point in Kerbin's orbit, Aptur is only a day away with the right maneuver. The alternative trajectory would've involved reducing the satellite's periapsis down to the orbit of Mun, but this method is much faster.

The Kinesis stage takes over for the remainder of the ejection burn.

Unfortunately a serious oversight meant that contact with OOP1 was lost shortly before it exited Kerbin's SOI. However, its maneuvers were pre-programmed so it may still reach orbit of Aptur.

Telescopes confirm that OOP1 has reached orbit of Aptur successfully, making it the first spacecraft to orbit another moon of Sonnah. As expected, the Kinesis stage had plenty of fuel for these maneuvers and the space probe's own propulsion system wasn't required. However, we cannot currently receive any data from it due to the weak antennas. It is likely that a relay satellite will be sent to Aptur, as this should be cheaper than replacing all of the equipment on the probe. Otherwise, a crewed mission may be sent to modify OOP1 and allow it to transmit data to Kerbin.

Continuation of Serran 3

After thirty days in space, Valentina and Janmon prepare to return to Kerbin.

Spoiler

Undocking from the station.

De-orbiting.

The mission ended as expected, with a successful re-entry and splashdown. Athena 1 was also de-orbited, and burned up harmlessly in the upper atmosphere of Kerbin.

2

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It's time to set up a communications network to facilitate future missions. This first launch was originally supposed to be K-Comm 1, but was retroactively renamed. The rocket used was an ordinary Aptur-F rocket, but with the Kinesis upper stage inside the larger fairing.

Spoiler

Fairing separation.

Kinesis stage ignition.

After engine cutoff, a serious problem becomes apparent. The monopropellant for the attitude control system was not loaded onto the vehicle.

The space probe spun out of control and was destroyed on re-entry.

That was not a good start to the construction of a communications network.

Meanwhile, other space agencies have been popping up around Kerbin, and have managed to get some Kerbals into space. Unfortunately they haven't quite figured out the "returning them safely to Kerbin" part, so we've been contracted to send some rescue missions.

Serran 4

The original purpose of the Serran 4 mission was to use a new variant of the Serran spacecraft on a new rocket, and send some kerbals beyond Kerbin's SOI to fly by Mun. However, the rescue missions must come first. There are four kerbals launched by various other space agencies stranded in low Kerbin orbit, and they need to be rescued quickly before their life support systems fail. Serran 4, and the subsequent Serran 5 mission, both use rockets that were intended to ferry kerbals to future space stations. Instead, those space station missions are likely to be cancelled or postponed.

Spoiler

This is the first launch of a Serran spacecraft without any crew. Since we have to rescue four kerbals we can do it cheapest with two rockets, but that means both need to be flown autonomously. The probe core on board has been rigorously tested and should suffice for this mission, but an automatic rendezvous procedure has yet to be attempted.

After reaching orbit and conducting a few maneuvers, Serran 4 approaches the first stranded spacecraft. Lurigh Kerman is on board, and EVAs over to the Serran spacecraft.

Then several more orbital maneuvers are executed to rendezvous with the second stranded kerbal.

Megner Kerman is rescued.

De-orbit, re-entry, and landing were successful.

Serran 5

A second rescue mission. Serran 5 was intended to be a flyby mission of Eli, including deployment of a small cubesat, but this has been posponed to Serran 7.

Spoiler

Launch was nominal.

Valvan Kerman and Elidock Kerman were rescued.

And they returned to Kerbin safely.

All four rescued kerbals joined our space agency. Presumably being left in orbit to be rescued by someone else isn't something they appreciated much. This is quite good, actually, because hiring new kerbonauts has become increasingly expensive of late; our newest pilot, Katmund, was only convinced to join for a price far higher than even the cost of an entire Serran spacecraft plus launch vehicle (granted, it's quite a cheap spacecraft, but still).

K-Comm 1

Now that the rescue missions are done, we can go back to setting up a communications network.

Spoiler

Liftoff of K-Comm 1.

The spacecraft reached orbit successfully.

Commencing ejection burn.

Payload deployment.

The satellite's own engines complete the ejection burn.

Escaping Kerbin.

K-Comm 1 reaches its apoapsis, in an orbit between Serran and Eli.

This is its final orbit, and two more identical satellites are due to be launched into the same orbit with 120° separation.

K-Comm 2

K-Comm 2 is identical to K-Comm 1, and will be launched into the same orbit 120° behind K-Comm 1.

Spoiler

Commencing Kerbin ejection burn.

Leaving Kerbin.

Circularizing.

Unfortunately, once K-Comm 2 reached apoapsis, it was realized that there was no connection between the two relay probes. It turned out that engineers had been reading the instructions upside-down, and the high-gain antennas on the relay satellites can only point to the deep space network antenna stations on Kerbin. Replacements will have to be sent.

Interestingly, due to an odd space-time anomaly [I added Asclepius to the system and Kopernicus did some strange things] both of the existing K-Comm satellites were teleported to a solar orbit some time after being placed in their orbit of Sonnah, and communication with them was lost.

4

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After a bit of a hiatus, I'm back in the New Horizons system. Despite the space-time anomaly kicking our useless communication satellites into a solar orbit, exploration plans continue. I've rethought (rethinked? rethunk?) my ideas of exactly how to do space exploration with Kerbalism considered, and I think I have some plans. Here's the current agenda:

Probe landings on Aptur, Mun, Eli, and Serran (most likely in that order)

Communications network set up around Serran (all satellites will have both low-gain and high-gain equipment for communication with surface-based and orbital equipment)

Assemble a more permanent space station in Kerbin orbit

Crewed landings on Aptur, Mun, and Eli (probably in that order)

Assemble a space station in Serran orbit

Crewed landings on Serran

Send first interplanetary space probes to study Laythe and the newly-discovered planet Asclepius

The key here is exploring Serran. The reason is because it has an oxygen-rich atmosphere, and telescope data shows that the same can be said of Laythe and Asclepius, so studying it will be useful for dealing with those two planets (which interestingly orbit the sun directly opposite each other).

The station in Serran orbit will be a fairly significant endeavour; it should have several modules and will need to support two teams of kerbals for quite a while. It will serve as a more local mission control center to avoid the brief-but-noticeable signal delay when communicating to Kerbin and back, as well as being a link to surface operations even when Kerbin is on the other side of Sonnah.

I want to accomplish crewed landings on Serran in two significant regions. There are big visual differences in appearance on some of Serran's terrain, and it's important to study both types of regolith to understand exactly what is going on. It's also likely that a glider probe will be sent to test the practicality of that landing method, which will include atmospheric tests as well as a jet engine to see whether flight is an effective method of transportation on the moon. If surface operations at Serran continue for long enough, the station will be expanded to sustain a third team of kerbals, and a ground base will be established in an area of interest (which will be found with telescopes sent to Serran orbit).

I will, of course, have to design new spacecraft and launch vehicles to accomplish all of this, but that should bring about no major difficulty. The toughest thing to do will be to make a crewed spacecraft capable of sending kerbals to Serran (though perhaps the lander will pose similar difficulty).

Valentina and Debdan sit in the Serran 6 spacecraft atop a Titanus 1 rocket. This three-stage rocket is designed for a slightly-smaller payload than Serran 6, though its integrated Dynamo stage will provide the rest of the delta-v required to reach Kerbin orbit - as well as most of the delta-v required for the trans-Munar burn. Serran 6 is designed to fly by the Mun on a fast trajectory to limit time spent in Sonnah orbit; the most fuel-efficient transfer would take twice as long before the crew could return to Kerbin (though two Munar flybys might be possible if done in that way). This quick trajectory also means line-of-sight communications with Kerbin at all times, which is useful but not technically necessary as the vehicle could potentially operate autonomously. It will probably be the most practical method of conducting a crewed Mun landing, as less mass for supplies means more mass available for a lander.

Spoiler

Ignition. The first stage of the Titanus 1 rocket uses 8 clustered Fulcrum engines, for a total of over 2.5 meganewtons of maximum vacuum thrust. The outer four engines can gimbal while the inner ones can't.

Liftoff.

First stage performs as expected.

First stage cutoff and separation.

Second stage ignition.

The second stage of the Titanus 1 rocket uses a Moa engine. This powerful mid-range engine is best used as an upper stage for launch vehicles, but its power and versatility means that it is likely to find other uses in future.

The third stage of the Titanus 1 rocket is a Kerberos stage. It's powered by a single Swivel engine and includes integrated RCS systems as well as a decoupler, and is designed for use in a variety of situations. It could potentially be added to the top of a larger rocket to be used as a transfer stage for sending payloads beyond Kerbin orbit (the same purpose the Dynamo stage will serve for Serran 6).

Third stage cutoff, nosecone separation, instrument deployment, third stage separation. The service module on the Serran 6 spacecraft is in two parts, unlike previous spacecraft in the Serran program. The rear section houses the propulsion module, while the forward section contains extended life support systems, science equipment, and a pair of solar panels identical to those used on the Athena 1 space station.

Sonnah is in the perfect position for pictures.

Transfer stage ignition.

The transfer stage circularized, and then was shut down as the Mun is not in quite the right position for the transfer yet.

Just outside of Kerbin's sphere of influence. This is the furthest from Kerbin any kerbals have ever been before. Debdan conducts an EVA, and checks that the science equipment is functioning properly.

After a few days, the Mun is in sight.

Just on the edge of the Munar SOI.

The flyby will approach the large crater on the Munar surface. It is a likely landing site for future exploration.

As the flyby reaches periapsis, it also approaches the day/night terminator. Though communication connection will not be lost due to a convenient coincidence the carefully-plotted trajectory, Valentina and Debdan will leave the Mun in darkness.

The dark side of the Mun.

A correction burn at Sonnah periapsis modifies the trajectory to achieve a good Kerbin intercept.

After quite a while in orbit, Serran 6 approaches Kerbin.

Unfortunately the re-entry will take place in the dark.

The spacecraft experienced a punishing acceleration of 8.8g on re-entry, which was even enough to knock Debdan unconscious and pushed Valentina to her limits. However, the crew suffered no long-term detriment and the heat shield actually fared better than predicted - it could probably stand up to a re-entry from interplanetary velocities if necessary, although this would best be avoided under usual circumstances.

Re-entry and splashdown were successful, and thanks to another coincidence the well-planned mission profile, the capsule was recovered only 4.6km away from the KSC.

This mission included a lot of firsts. First kerbals outside of Kerbin orbit, first kerbals to fly by another moon of Sonnah, closest periapsis of Sonnah achieved by anything artificial so far, first flyby of the Mun, and the first return from beyond Sonnah's sphere of influence. It was also useful for proving that the capabilities of the existing Serran command module are sufficient for missions to Sonnah's other moons and back - though additional supplies will be required to reach Eli or Serran.

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This is the first module of the new Athena 2 space station. This launch will send up the A1 module, which includes power and propellant storage as well as the station avionics.

Spoiler

Liftoff of Athena 2 A1.

Launch went as expected.

After fairing deployment.

Circularizing.

After a few maneuvers, the station module is placed in a 1000km orbit, and the upper stage of the launch vehicle separates.

Graviton 1

Graviton 1 is a simple satellite designed to study Kerbin's gravitational field. It is launched on an Aptur-F rocket, and is probably the last payload to be launched on this type of rocket as the technology is becoming outdated.

Spoiler

Liftoff of Graviton 1.

The Kinesis upper stage has been slightly modified for this launch to assist with control. Despite this, the launch vehicle suffers from poor roll control after jettison of the half-stage. This is a large part of the reason that the rocket is being abandoned in favour of new designs.

The payload's antennae deploy.

After circularization, the payload is deployed.

A few maneuvers with its small propulsion module place it into its correct orbit, after which the propulsion module is jettisoned so that the delicate instrumentation is not affected by it. The probe also relies on reaction wheels for stability control as RCS thrusters could compromise the science results.

Small Step 1

It is finally time for the first landing on another celestial body. Small Step 1 is a two-part spacecraft, consisting of an orbiter and a lander, that will gather the first close-up science data from Aptur. It is launched on a Titanus 1 rocket.

Spoiler

Liftoff of Small Step 1.

About two-thirds of the way through the first-stage burn, one of the center four engines lost thrust and was shut down. Luckily the engine layout allows for the vehicle to compensate for such a loss of thrust, although the rocket did lose some altitude.

The second stage has to burn more radial than would be ideal to ensure that the apoapsis continues to rise. This put considerable strain on the fairing, which almost melted. The launch trajectory may need some rethinking for future missions in case of a similar engine failure.

Second stage cutoff and fairing separation.

Payload antennae deployment.

The second stage begins the circularization burn.

Second stage cutoff and separation.

Third stage ignition. Circularization was completed by the Kerberos MPRS (Multi-Purpose Rocket Stage).

Several orbits later, the moons are aligned ideally for the transfer. The Kerberos stage completes the transfer burn.

As the probe leaves Kerbin, it passes through the shadow. Here Aptur can be seen - it's that tiny black dot on the left.

A single correction burn puts the spacecraft on a low flyby trajectory of Aptur.

Approaching Aptur.

MPRS separation.

Payload adapter separation. Both the Kerberos MPRS and the payload adapter will collide with Aptur.

Making a small radial burn to correct the periapsis. Aptur has incredibly uneven terrain, but a 65km periapsis has been deemed safe.

This rock looks a whole lot bigger up close.

Commencing orbital capture. The orbiter will remain in a 65km by 170km orbit.

This is what Kerbin looks like from here.

Finalizing capture burn.

Small Step 1 has successfully reached orbit of Aptur. You may be wondering at this point where exactly the lander is.

Spacecraft separation complete.

The lander moves away from the orbiter.

An orbit later, and after de-orbiting, the Small Step 1 lander descends towards the surface of Aptur.

With no engine gimbal and no reaction wheels, the lander relies entirely on the RCS thrusters for control. The low mass makes this a particularly effective method even with just a small thruster block.

Final descent. Everything has gone as expected so far.

Touchdown. Small Step 1 has successfully landed on Aptur. It will transmit the data from the on-board experiments for quite some time.

The orbiter portion of the mission has its own instruments. Magnetometer data seems to indicate a particularly strange effect on Sonnah's magnetic fields; further study will be needed.

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I see you mentioning orbital decay here. Is that a mod or just a low persistent debris threshold?

It's "if the debris has a low enough periapsis I can delete it from the tracking station after a while without feeling like I should've left it in space". Mostly because I'm trying to get a reasonable amount of realism even if some of it is simulated (similar with tuning down the reaction wheels) but also because I don't want to leave too much debris around to avoid lag. I'd leave stuff in orbit most of the time if I had a more powerful computer, but I already get a pretty bad framerate sometimes with this mod set (mostly during ascent).

Usually I try to de-orbit stuff more legitimately (like the transfer stage for Small Step 1, which I crashed into Aptur intentionally) but sometimes that doesn't quite work out (like with ascent stages which only just reach orbit).

The Serran spacecraft has proven to be very effective at completing missions as part of the Serran program. However, it is very cramped, only seats two kerbals, and does not have the supplies to last on a journey to any of Sonnah's other moons without a specialized service module. Therefore, it is important to design a replacement for it to use after the Serran program is complete.

This is the purpose for which the Pegasus spacecraft has been designed. Pegasus uses a common command module for several different spacecraft, each with a unique (yet versatile) purpose. The crewed Pegasus variants can each sustain 3 kerbals for various amounts of time, and have integrated cargo space which the Serran spacecraft lacked. The capsule can also be used with little modification as part of an atmospheric lander (though the actual lander vehicle will have to be designed separately). They will also be solar-powered (once the necessary solar technology is developed properly), allowing them to have as long a mission time as is required, provided the crew's supplies will last long enough.

PPM1

The first test of a prototype Pegasus vehicle will be an in-flight test of the fairing separation mechanism and landing systems. For this purpose, a prototype of the Pegasus-LD variant is loaded onto a simple solid rocket motor inside its launch fairing. This test will simulate a steep ascent trajectory with higher accelerations than are expected in an ordinary launch, and will test the mechanism by which the Pegasus command module separates from the surrounding spacecraft in the event of a launch abort.

Spoiler

Liftoff of PPM1 (Pegasus Prototype Mission 1).

SRM cutoff.

Fairing separation. Immediately an issue is apparent. The fairing was not separated with enough force, and collided with (and destroyed) the orbital module. This will be fixed in later iterations.

The rest of the spacecraft appears to be intact. What's important is that the command module survived unscathed. The fairing shouldn't separate this early in flight, but if it does it will be during a launch abort, so it is vital that this mechanism works perfectly.

Command module separation. The explosion this time was due to a collision with the solid rocket motor due to the low-thrust separation event. This isn't a problem which will occur on a launch of the complete spacecraft, because separation motors (or the LES) will provide high enough thrust to avoid such an issue.

The command module remains unscathed. Its shape means that it will be forced into the correct position for atmospheric entry (although with the 51km apoapsis of this flight, it is still technically in the atmosphere.

Drogue chutes deployed successfully.

Drogue chutes cut. Main chutes deployed successfully.

Full parachute deployment successful.

Splashdown successful.

Though it wasn't an entirely successful flight, the issues encountered now provide engineers with an opportunity to fix things so that the same issues do not occur in future launches.

PPM2

PPM2 is a pad test of the abort sequence. Issues found in PPM1 have been fixed, so the fairing should separate cleanly.

The abort sequence is as follows:

Abort command given.

Fairing separation, followed almost immediately by abort motor ignition and service module separation.

Abort motor cutoff and separation.

LES connector separation.

Orbital module separation.

Landing sequence start.

Spoiler

Fairing separation, abort motor ignition, service module separation.

Abort motor cutoff and separation, LES connector separation.

Orbital module separation and landing sequence start.

Landing successful.

A perfectly successful test of the Pegasus abort system.

Technical Specification: Pegasus Variants

Pegasus LD

Spoiler

Pegasus LD (Long Duration) is designed to sustain 3 kerbals for up to half a year. If docked with a larger supply module, it could be suitable for the entire duration of a flyby of any of the nearest planets to Sonnah.

Components, from the front:

Launch Escape System. A solid rocket motor designed to propel the command module away from the rocket in the event of a launch abort.

Orbital module. An extended habitat to give the crew some extra living space during long-duration missions.

Command module. Where the crew will be during launch and landing. Contains all spacecraft control equipment as well as some of the life support systems.

LD service module. The long-duration service module contains propellant, propulsion systems, and power systems for the spacecraft, as well as supplies for the crew and space for small cargoes (such as science equipment). The final version will have solar panels.

Pegasus SD

Spoiler

Pegasus SD (Short Duration) is designed for short excursions. In this configuration it will be mostly used to transport kerbals to/from Kerbin orbit, though with the addition of extra supplies in the service module it could be used for transport between Sonnah's moons.

Components, from the front:

Launch Escape System. A solid rocket motor designed to propel the command module away from the rocket in the event of a launch abort.

Command module. Where the crew will be during launch and landing. Contains all spacecraft control equipment as well as some of the life support systems.

SD service module. Contains propellant and propulsion systems. Will also include power systems and a small amount of cargo space.

Pegasus C

Spoiler

Pegasus C (Cargo) is an uncrewed Pegasus variant. It is mostly intended for station resupply missions, though could potentially have other applications (such as landing payloads on an atmospheric world).

Modules, from the front:

Launch Escape System. A solid rocket motor designed to propel the payload module away from the rocket in the event of a launch abort. The reason this is present on an uncrewed vehicle is so that the payload module and the payload can be recovered, potentially saving a large amount of funds from a failed launch.

Payload module. Either uses a pressurized cargo module for station supplies, or a non-pressurized cargo bay with a non-recoverable fairing. Designed to survive atmospheric entry even if fairing is removed. Sophisticated instrumentation allows the spacecraft to operate almost entirely autonomously.

SD service module. Contains propellant and propulsion systems. Will also include power systems and a small amount of cargo space.

I'd appreciate hearing what people thing about this technical report. Should I do more of these every so often, or should I just focus on the main series of missions?

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I kinda like seeing the details of ships if those ships are going to become familiar parts of the story. With me, however, technology marches on so I hardly ever use the same design more than once.

I always use vehicles several times, unless they're an extremely specific design (like Small Step 1). But even then I'll reuse the same kinds of ideas even if it's not an identical vehicle (the rest of the Small Step orbiter/lander vehicles will look different but work identically).

The Pegasus spacecraft won't be used until after the Serran program is complete, but I've started testing them now to make sure they're perfect when I need them. They'll be my main crew spacecraft pretty much indefinitely once the Serran spacecraft are retired. Similarly, I'm in the middle of the design phase for both the remaining Titanus rockets and the future Titanus Heavy rockets (basically my Saturns; they'll be comparable in functionality) despite not being likely to need anything larger than Titanus 3 for the remainder of the Serran program.

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I also like incorporating standardized craft programs that can be improved upon and retired as necessary. Aside from the "space program role-play" aspect of it, when you're very familiar with the left and right limits of a craft's capabilities, you can select the right craft for the right mission with confidence. And it's interesting to see what craft you find yourself using down the road, and which designs you put in the corner to gather dust. That in itself is a strong indicator of solid engineering.

Kinda like certain iconic aircraft in the world like the Piper Cub, Cessna 172, Huey, or Mi-8. Sometimes rugged and simple to use and maintain wins out over bells and whistles.

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Are you playing with Kerbalism radiation turned on? If so, how nasty are the belts around such a big gas giant? What was the total mission time for that first Münar flyby?

I do have radiation turned on. I haven't actually had any trouble with Sonnah's magnetic field yet though; the regions of strong radiation are mostly not where I've needed to fly yet. And anyway, Sonnah isn't too large a gas giant. I'm sure when I go to Jool I'll have more difficulty with the magnetic fields.

As for the mission time for Serran 6, I've actually forgotten. I think it was about 14 or 15 days (measured in stock days, though the rescale doubles the length of days everywhere) but I'm not 100% sure. I'll start keeping track of mission duration better in future though.